You have difficulty because you think you should explain why you lied. This is the fact: you lied, trying to explain your boyfriend not coming. You are still stuck in old patterns. You want to blame your mom for you telling him not to come (and then not informing her). This is how you tell your mom: “Mom, I lied when I said he wasn’t feeling well. The truth is that I told him not to come.” Don’t give a reason unless she asks. Tell her it was wrong for you not to tell her he was not coming, perhaps that you understand why she was angry, because I think you do, and she explained it to you. I assume you are not living with your parents. (If you are, this is much more complicated). In any case, the only way forward is with the truth and no excuses or “reasons.” — unless asked, and even then be careful. As children, we learned to make excuses. If we had a good excuse, it was okay. But it wasn’t okay, and that never really worked well. Lying makes your life complicated. Keep it simple.